Last friday I was driving out of town and my truck completly fell on its face. (its a 93 f-150 5.8l 4x4) At first I thought it was bad gas b/c I just purchased a full tank before heading out. I have 2 tanks so I switched to the other one and it still ran like crap. So I bought a couple cans of heet and tried that, didnt help. I eventually made it home but it was horrible. The truck seemed like it was running on 3 cylinders the whole time and took about 2mins to get up to 55mph. I hated driving it like that but its all I could do. I put a new fuel filter on and used a pressure guage to check the pumps and there fine. Then I had a friend come to the house cause he has a diagnostic computer, and it said a couple different things. 412 cannot raise rpm, 116 coolant temp (ect) sensor out of range, 126 map board out of range, 172 EGO not switching lean EXH (bank #1), 213 spout circuit open. So theres a few thing goin on, anyways he thought it is the map sensor which is 70 bucks. Im really not sure if i wanna go buy that or trailer the truck into town to a mechanic. I talked to a few other people and they think its the colant temp sensor but I cant seem to find where its located, but anyways I will appriciate any help on this problem

 

first and cheapest things first... thermostat.. they do go bad... then coolent sensor. Not your temp gauge.. but the coolant sensor that the computer sees. Then clean your MAF. The TPS could cause the can't raise rpm code.... the map sensor goes bad now and then too. It will cost you money either way.. change the sensors you can yourself first and save some money. If it was my truck, I would change the MAP sensor first.

 

Here is some info you need to consider;
In looking at the codes, there are common things to most all them.
Looking at the system layout, they all have common signal return and most have common VREF power. THIS IS NOT GROUND TO THE CHASSIS but solely from and to the EEC. Don't check voltage to chassis ground or it will be wrong.
My feeling is you have a harness fault that disrupts many functions at the same time hence the very poor running.
I would first get the engine running if possible then move the harnesses around to see if there is a cross, a rubthru or there is any reactions to movements.
Next, voltage checks for VREF to signal return common to sensors that are involved with the codes.
Since the Ox sensor is involved it may be reacting to poor fueling condition and clear when the fault is found.
This is one of those times it pays to have some deeper level of information in order to find the fault or a large stroke of luck.
The older trucks are now suseptable to harness faults.
The IAC, ECT, TPS, EVP, MAP, OX, are common on signal return.
The Spout is a seperate item so there is a possibility the PIP or the TFI in the dist is faulty. The PIP controls everything.
Spout open means the EEC can't control ignition timing thru the TFI control.
Look for the problem with these things in mind and pin it down before replacing parts as much as possible.
Good luck with it.

 

ok well my dad knows a guy that owns a local junk yard and he will allow me to take any sensors off of a truck like mine and try them before I pay for them. So what sensors should I try 1st, and if you could describe the location that would be great. Ive been looking for the ect, or thermistor whatever it is, and cant seem to find it. I also am not sure which one is the map sensor. I need to take my sensors off so I can show the guy at the junk yard what i need. Thanks

 

can anybody help????